Microcapsules Containing Active Ingredients

ABSTRACT

The present invention relates to a microcapsule particle composition that is composed of a sol-gel material. The microcapsule particle composition is well suited for personal care and cleaning products.

STATUS OF RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 12/328,340,filed Dec. 4, 2008, the contents hereby incorporated by reference as ifset forth in its entirety.

FIELD OF THE INVENTION

The present invention relates to active materials that are encapsulatedwith a sol-gel material. The microcapsule particle composition is wellsuited for applications associated with personal care and cleaningproducts.

BACKGROUND OF THE INVENTION

Fragrance chemicals are used in numerous products to enhance theconsumer's enjoyment of a product. Fragrance chemicals are added toconsumer products such as laundry detergents, fabric softeners, soaps,detergents, personal care products, such as but not limited to shampoos,body washes, deodorants and the like, as well as numerous otherproducts.

In order to enhance the effectiveness of the fragrance materials for theuser, various technologies have been employed to enhance the delivery ofthe fragrance materials at the desired time. One widely used technologyis encapsulation of the fragrance material in a protective coating.Frequently the protective coating is a polymeric material. The polymericmaterial is used to protect the fragrance material from evaporation,reaction, oxidation or otherwise dissipating prior to use. A briefoverview of polymeric encapsulated fragrance materials is disclosed inthe following U.S. patents: U.S. Pat. No. 4,081,384 discloses a softeneror anti-stat core coated by a polycondensate suitable for use in afabric conditioner; U.S. Pat. No. 5,112,688 discloses selected fragrancematerials having the proper volatility to be coated by coacervation withmicro particles in a wall that can be activated for use in fabricconditioning; U.S. Pat. No. 5,145,842 discloses a solid core of a fattyalcohol, ester, or other solid plus a fragrance coated by an aminoplastshell; and U.S. Pat. No. 6,248,703 discloses various agents includingfragrance in an aminoplast shell that is included in an extruded barsoap.

While encapsulation of fragrance in a polymeric shell can help preventfragrance degradation and loss, it is often not sufficient tosignificantly improve fragrance performance in consumer products.Therefore, methods of aiding the deposition of encapsulated fragranceshave been disclosed. U.S. Pat. No. 4,234,627 discloses a liquidfragrance coated with an aminoplast shell further coated by a waterinsoluble meltable cationic coating in order to improve the depositionof capsules from fabric conditioners. U.S. Pat. No. 6,194,375 disclosesthe use of hydrolyzed polyvinyl alcohol to aid deposition offragrance-polymer particles from wash products. U.S. Pat. No. 6,329,057discloses use of materials having free hydroxy groups or pendantcationic groups to aid in the deposition of fragranced solid particlesfrom consumer products.

In addition, the prior art discloses the use of silica to formmicrocapsule formulations specifically designed to prevent anencapsulated active ingredient from leaving the microcapsule. This isdesirable when the active ingredient is an irritant to the body tissueto which it is applied. It is also is desired when the active ingredientacts by interaction with light, such as sunlight. However, U.S. Pat. No.6,303,149 fails to disclose compositions and methods for releasing andhence delivering the active ingredients. Despite these and many otherdisclosures there is an ongoing need for the improved delivery offragrance materials for various personal care products, rinse-offproducts and leave-on products that provide improved performance.

SUMMARY OF THE INVENTION

According to the present invention a process is provided for preparingmicrocapsule particle composition having a core material encapsulatedwithin a microcapsular shell. The core material may contain at least oneactive ingredient, such as but not limited to a fragrance. The processcomprises the steps of first mixing an appropriate amount sol-gelprecursor and fragrance oil, followed by cooling of the mixtureobtained. The next step in the process is to prepare a surfactantsolution by dissolving an appropriate amount of surfactant in water andthen cooling the surfactant solution. In the next step the sol-gelprecursor and fragrance oil are added to the surfactant solution andthen the mixture is homogenized. A defoamer is added as needed and themixture is allowed to cure to form the microcapsule particlecomposition.

In another embodiment, a process is provided for preparing microcapsuleparticle composition having a core material encapsulated within amicrocapsular shell. The core material may contain at least one activeingredient such as but not limited to a fragrance. In the first step ofthe process a fragrance oil is added to an aqueous surfactant solution.The mixture is homogenized to form a fragrance emulsion and then sol-gelprecursor is added dropwise to the fragrance emulsion under continuousmixing. The final mixture is allowed to cure at room temperature to formthe microcapsule particle composition.

In yet another embodiment, a process for preparing microcapsule particlecomposition having a core material encapsulated within a microcapsularshell is provided. The microcapsules prepared according to this processmay contain a core material, which may contain at least one activeingredient such as, but not limited to a fragrance. The first step ofthe process is to add an appropriate amount of fragrance oil to anaqueous surfactant solution and then homogenize the mixture to form afragrance emulsion. An appropriate amount of water is added to thefragrance emulsion to achieve the desired concentration. Then anappropriate amount of sol-gel precursor is added to the to the dilutedfragrance emulsion dropwise under constant mixing. The mixture is thenallowed to cure at room temperature until the microcapsule particlecomposition is formed.

In still another embodiment a process is provided for preparing amicrocapsule particle composition having a core material encapsulatedwithin a microcapsular shell. The core material comprises at least oneactive ingredient such as but not limited to a fragrance. The first stepof the process is to prepare a fragrance emulsion by emulsifying anappropriate amount of fragrance oil into surfactant solution. The secondstep is to prepare a sol-gel precursor emulsion by emulsifying anappropriate amount of sol-gel precursor and an aqueous surfactantsolution. The next step is to add the sol-gel precursor emulsion to thefragrance emulsion under constant mixing and then allow the finalmixture to cure at room temperature until capsule have formed

In an additional embodiment of the invention there a process is providedfor preparing microcapsule particle composition having a core materialencapsulated within a microcapsular shell, wherein the core material maycontain at least one active ingredient such as but not limited tofragrance oil. The process comprises the steps of adding fragrance oilto an aqueous surfactant and homogenizing the mixture to provide afragrance emulsion. An appropriate amount of water is added to thefragrance emulsion to achieve the desired concentration. The next stepin the process is to prepare a sol-gel precursor emulsion by emulsifyingsol-gel precursor into an aqueous surfactant solution. The sol-gelprecursor emulsion is then added to the fragrance emulsion underconstant mixing and then allowed to cure at room temperature untilcapsules have formed.

In another embodiment of the invention, a microcapsule particlecomposition having a core material encapsulated within a microcapsularshell is provided. According to this embodiment the wall material of themicrocapsule is composed of a sol-gel precursor.

In yet a further embodiment a personal care composition containing themicrocapsule composition is provided.

In still a further embodiment a personal care product is providedcontaining the microcapsule composition of the present invention.

In an embodiment of the invention a process is provided for preparing asilica microcapsule composition modified with a second spherecomplexation.

The second sphere complexation may be selected from polyethyleneiminePEI, an amine oxide, cocoamidopropylamine oxide, ammonium lauryl ethersulfate, inorganic zinc oxide and mixtures thereof.

The modified capsule in the current invention delivers superior consumerbefits when compared to the use of neat fragrance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. Optical microscopy image of standard silica capsules dispersedin DI H₂O as fresh sample.

FIG. 2. Optical microscopy image of standard silica capsules driedovernight on glass slide shows complete breakage.

FIG. 3. SEM image of dried standard silica capsules shows breakage.

FIG. 4. Optical microscopy image of polyethyleneimine treated silicacapsules dried overnight on glass slide.

FIG. 5. SEM image of dried polyethyleneimine treated silica capsules

FIG. 6. Optical microscopy image of cocoamidopropylamine oxideSpecial-treated silica capsules, 4 days after drying on glass slide.

FIG. 7. SEM of dried cocoamidopropylamine oxide special-treated silicacapsules

FIG. 8. Optical microscopy image of zinc oxide special-treated silicacapsules, 3 days after drying on glass slide

FIG. 9. Optical microscopy image of ammonium lauryl ethersulfate-treated silica capsules, 4 days after drying on glass slide.

DETAILED DESCRIPTION OF THE INVENTION

According to the present invention a process is provided for preparingmicrocapsule particle composition, having a core material encapsulatedwithin a microcapsular shell. The core material comprises at least oneactive ingredient, such as but not limited to a fragrance. The processcomprises the steps of first mixing an appropriate amount sol-gelprecursor and fragrance oil, followed by cooling of the mixtureobtained. The next step in the process is to prepare a surfactantsolution by dissolving an appropriate amount of surfactant in water andthen cooling the surfactant solution. In the next step the sol-gelprecursor and fragrance oil are added to the surfactant solution andthen the mixture is homogenized. A defoamer is added as needed and themixture is allowed to cure to form the capsule particles.

In another embodiment, a process is provided for preparing microcapsuleparticle composition having a core material encapsulated within amicrocapsular shell, wherein the core material may contain at least oneactive ingredient such as but not limited to a fragrance. In the firststep of the process a fragrance oil is added to an aqueous surfactantsolution. The mixture is homogenized to form a fragrance emulsion andthen sol-gel precursor is added dropwise to the fragrance emulsion undercontinuous mixing. The final mixture is allowed to cure at roomtemperature to form capsule particles.

In yet another embodiment, a process for preparing microcapsule particlecomposition having a core material encapsulated within a microcapsularshell is provided. The microcapsules prepared according to this processmay contain at least one active ingredient such as but not limited to afragrance. The first step of the process is to add an appropriate amountof fragrance oil to an aqueous surfactant solution and then homogenizethe mixture to form a fragrance emulsion. An appropriate amount of wateris added to the fragrance emulsion to achieve the desired concentration.Then an appropriate amount of sol-gel precursor is added to the to thediluted fragrance emulsion dropwise under constant mixing. The mixtureis then allowed to cure at room temperature until capsules are formed.

In still another embodiment a process is provided for preparingmicrocapsules having a core material encapsulated within a microcapsularshell, wherein the core material comprises at least one activeingredient such as but not limited to a fragrance. The first step of theprocess is to prepare a fragrance emulsion by emulsifying an appropriateamount of fragrance oil into surfactant solution. The second step is toprepare a sol-gel precursor emulsion by emulsifying an appropriateamount of sol-gel precursor and an aqueous surfactant solution. The nextstep is to add the sol-gel precursor emulsion to the fragrance emulsionunder constant mixing and then allow the final mixture to cure at roomtemperature until capsule have formed

In an additional embodiment of the invention a process is provided forpreparing microcapsule particle composition having a core materialencapsulated within a microcapsule shell, wherein the core materialcomprises at least one active ingredient such as, but not limited tofragrance oil. The process comprises the steps of adding fragrance oilto an aqueous surfactant and homogenizing the mixture to provide afragrance emulsion. An appropriate amount of water is added to thefragrance emulsion to achieve the desired concentration. The next stepin the process is to prepare a sol-gel precursor emulsion by emulsifyingsol-gel precursor into an aqueous surfactant solution. The sol-gelprecursor emulsion is then added to the fragrance emulsion underconstant mixing and then allowed to cure at room temperature untilcapsules have formed.

In an embodiment of the invention a process is provided for preparing asilica microcapsule particle composition with a second spherecomplexation.

The second sphere complexation may be selected from polyethyleneiminePEI, an amine oxide, cocoamidopropylamine oxide, ammonium lauryl ethersulfate, inorganic zinc oxide and mixtures thereof.

According to one embodiment of the present invention, the core materialmay contain an active ingredient, such as, but not limited to afragrance. The fragrances suitable for use in this invention includewithout limitation, any combination of fragrance, essential oil, plantextract or mixture thereof that is compatible with, and capable of beingencapsulated by a monomer or a polymer.

Many types of fragrances can be employed in the present invention, theonly limitation being the compatibility and ability to be encapsulatedby the polymer being employed, and compatibility with the encapsulationprocess used. Suitable fragrances include but are not limited to fruitssuch as almond, apple, cherry, grape, pear, pineapple, orange,strawberry, raspberry; musk, flower scents such as lavender-like,rose-like, iris-like, and carnation-like. Other pleasant scents includeherbal scents such as rosemary, thyme, and sage; and woodland scentsderived from pine, spruce and other forest smells. Fragrances may alsobe derived from various oils, such as essential oils, or from plantmaterials such as peppermint, spearmint and the like. Other familiar andpopular smells can also be employed such as baby powder, popcorn, pizza,cotton candy and the like in the present invention.

A list of suitable fragrances is provided in U.S. Pat. Nos. 4,534,891,5,112,688 and 5,145,842. Another source of suitable fragrances is foundin Perfumes Cosmetics and Soaps, Second Edition, edited by W. A.Poucher, 1959. Among the fragrances provided in this treatise areacacia, cassie, chypre, cylamen, fern, gardenia, hawthorn, heliotrope,honeysuckle, hyacinth, jasmine, lilac, lily, magnolia, mimosa,narcissus, freshly-cut hay, orange blossom, orchids, reseda, sweet pea,trefle, tuberose, vanilla, violet, wallflower, and the like.

As used herein olfactory effective amount is understood to mean theamount of compound in perfume compositions the individual component willcontribute to its particular olfactory characteristics, but theolfactory effect of the fragrance composition will be the sum of theeffects of each of the fragrance ingredients. Thus the compounds of theinvention can be used to alter the aroma characteristics of the perfumecomposition by modifying the olfactory reaction contributed by anotheringredient in the composition. The amount will vary depending on manyfactors including other ingredients, their relative amounts and theeffect that is desired.

The level of fragrance in the microcapsule varies from about 5 to about95 weight percent, preferably from about 30 to about 95 and mostpreferably from about 50 to about 90 weight percent on a dry basis. Inaddition to the fragrance other agents can be used in conjunction withthe fragrance and are understood to be included.

As noted above, the fragrance may also be combined with a variety ofsolvents which serve to increase the compatibility of the variousmaterials, increase the overall hydrophobicity of the blend, influencethe vapor pressure of the materials, or serve to structure the blend.Solvents performing these functions are well known in the art andinclude mineral oils, triglyceride oils, silicone oils, fats, waxes,fatty alcohols, diisodecyl adipate, and diethyl phthalate among others.

A common feature of many encapsulation processes is that they requirethe fragrance material to be encapsulated to be dispersed in aqueoussolutions of polymers, pre-condensates, surfactants, and the like priorto formation of the capsule walls. Therefore, materials having lowsolubility in water, such as highly hydrophobic materials are preferred,as they will tend to remain in the dispersed perfume phase and partitiononly slightly into the aqueous solution. Fragrance materials with Clog Pvalues greater than 1, preferably greater than 3, and most preferablygreater than 5 will thus result in micro-capsules that contain coresmost similar to the original composition, and will have less possibilityof reacting with materials that form the capsule shell. Surfactantscontemplated for use in the present invention may be anionic, nonionicor cationic surfactants.

One object of the present invention is to deposit capsules containingfragrance cores on desired substrates such as cloth, hair, and skinduring washing and rinsing processes. Further, it is desired that, oncedeposited, the capsules release the encapsulated fragrance either bydiffusion through the capsule wall, via small cracks or imperfections inthe capsule wall caused by drying, physical, or mechanical means, or bylarge-scale rupture of the capsule wall. In each of these cases, thevolatility of the encapsulated perfume materials is critical to both thespeed and duration of release, which in turn control consumerperception. Thus, fragrance chemicals which have higher volatility asevidenced by normal boiling points of less than 250° C., preferably lessthan about 225° C. are preferred in cases where quick release and impactof fragrance is desired. Conversely, fragrance chemicals that have lowervolatility (boiling points greater than 225° C.) are preferred when alonger duration of aroma is desired. Of course, fragrance chemicalshaving varying volatility may be combined in any proportions to achievethe desired speed and duration of perception.

In order to provide the highest fragrance impact from the fragranceencapsulated capsules deposited on the various substrates referencedabove, it is preferred that materials with a high odor-activity be used.Materials with high odor-activity can be detected by sensory receptorsat low concentrations in air, thus providing high fragrance perceptionfrom low levels of deposited capsules. This property must be balancedwith the volatility as described above. Some of the principles mentionedabove are disclosed in U.S. Pat. No. 5,112,688.

The following fragrance ingredients provided in Table I are among thosesuitable for inclusion within the capsule of the present invention:

TABLE I PERFUME INGREDIENTS CLOGP Allyl cyclohexane propionate 3.935Ambrettolide 6.261 Amyl benzoate 3.417 Amyl cinnamate 3.771 Amylcinnamic aldehyde 4.324 Amyl cinnamic aldehyde dimethyl acetal 4.033Iso-amyl salicylate 4.601 Aurantiol (Trade name for Hydroxycitronellal-4.216 methylanthranilate) Benzyl salicylate 4.383 para-tert-Butylcyclohexyl acetate 4.019 Iso butyl quinoline 4.193 beta-Caryophyllene6.333 Cadinene 7.346 Cedrol 4.530 Cedryl acetate 5.436 Cedryl formate5.070 Cinnamyl cinnamate 5.480 Cyclohexyl salicylate 5.265 Cyclamenaldehyde 3.680 Diphenyl methane 4.059 Diphenyl oxide 4.240 Dodecalactone4.359 Iso E Super (Trade name for 1-(1,2,3,4,5,6,7,8- 3.455Octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)-ethanone) Ethylenebrassylate 4.554 Ethyl undecylenate 4.888 Exaltolide (Trade name for15-Hydroxyentadecanloic 5.346 acid, lactone) Galaxolide (Trade name for1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8- 5.482hexamethylcyclopenta-gamma-2-benzopyran) Geranyl anthranilate 4.216Geranyl phenyl acetate 5.233 Hexadecanolide 6.805 Hexenyl salicylate4.716 Hexyl cinnamic aldehyde 5.473 Hexyl salicylate 5.260 Alpha-Irone3.820 Lilial (Trade name for para-tertiary-Butyl-alpha-methyl 3.858hydrocinnamic aldehyde) Linalyl benzoate 5.233 Methyl dihydrojasmone4.843 Gamma-n-Methyl ionone 4.309 Musk indanone 5.458 Musk tibetine3.831 Oxahexadecanolide-10 4.336 Oxahexadecanolide-11 4.336 Patchoulialcohol 4.530 Phantolide (Trade name for 5-Acetyl-1,1,2,3,3,6-hexamethyl5.977 indan) Phenyl ethyl benzoate 4.058 Phenylethylphenylacetate 3.767Phenyl heptanol 3.478 Alpha-Santalol 3.800 Thibetolide (Trade name for15-Hydroxypentadecanoic acid, 6.246 lactone) Delta-Undecalactone 3.830Gamma-Undecalactone 4.140 Vetiveryl acetate 4.882 Ylangene 6.268 MethylBeta Napthyl Ketone 1.99 Terpeneol Couer 2.67 Geraniol 2.7Dihydromyrcenol 2.99 Citronellol 950 3.3 Tetrahydromyrcenol 3.54

The higher ClogP materials are preferred, meaning that those materialswith a ClogP value of 4.5 are preferred over those fragrance materialswith a ClogP of 4; and those materials are preferred over the fragrancematerials with a ClogP of 3.3.

The fragrance formulation of the present invention should have at leastabout 40 weight percent of materials with ClogP greater than 3.3,preferably greater than about 80 and more preferably greater than about90 weight percent of materials with ClogP greater than 4.

In an additional embodiment the fragrance formulation may containfragrance materials with a ClogP greater than about 1.5.

Those with skill in the art appreciate that fragrance formulations arefrequently complex mixtures of many fragrance ingredients. A perfumercommonly has several thousand fragrance chemicals to work from. Thosewith skill in the art appreciate that the present invention may containa single ingredient, but it is much more likely that the presentinvention will comprise at least eight or more fragrance chemicals, morelikely to contain twelve or more and often twenty or more fragrancechemicals. The present invention also contemplates the use of complexfragrance formulations containing fifty or more fragrance chemicals,seventy five or more or even a hundred or more fragrance chemicals in afragrance formulation.

Preferred fragrance materials will have both high ClogP and high vaporpressure. Among those having these properties are:

Para cymene, Caphene, Mandarinal Firm, Vivaldie, Terpinene, Verdox,Fenchyl acetate, Cyclohexyl isovalerate, Manzanate, Myrcene, Herbavert,Isobutyl isobutyrate, Tetrahydrocitral, Ocimene and Caryophyllene.

According to one embodiment of the invention, the microcapsule particlecomposition is well suited for personal care and cleaning products. Thepresent invention is also suitable for wash-off products, which areunderstood to be those products that are applied for a given period oftime and then are removed. Products suitable for this invention arecommon in areas such as laundry products, and include detergents, fabricconditioners, and the like; as well as personal care products whichinclude shampoos, hair rinses, body washes, soaps, hand sanitizers,anti-perspirants, deodorants and the like.

According to another embodiment of the invention the microcapsulecomposition is well suited for perfumes, eau de toilette and colognes.The appropriate carrier materials for the microcapsules in perfumes, eaude toilette and colognes include but are not limited to an aqueous orhydroalcoholic bases which includes alcohols such as ethanol, methanol,and the like; dipropylene glycol, dipropylene glycol ethers, diethylphthalate and isopropyl myristate. The level of water in these systemsis intentionally kept to a minimum, preferably below 5 weight percent ofthe fragrance composition, more preferably below 1 weight percent andmost preferably less than 0.1 weight percent. Persons with skill in theart will be able to formulate fragrance compositions within the scope ofthe present invention that contain no intentionally added water.

Example of a suitable polymeric stabilizing agents useful in the presentinvention include carbohydrate gums such as cellulose gum,microcrystalline cellulose, cellulose gel, hydroxyethyl cellulose,hydroxypropyl cellulose, sodium carboxymethylcellulose, hydroxymethylcarboxymethyl cellulose, carrageenan, hydroxymethyl carboxypropylcellulose, methyl cellulose, ethyl cellulose, guar gum (includingcationic guar gums such as Jaguar®), gum karaya, gum tragacanth, gumarabic, gum acacia, gum agar, xanthan gum and mixtures thereof.Preferred carbohydrate gums are the cellulose gums and xanthan gum.

In one embodiment, an anti-perspirant roll-on personal care product isprovided which contains an effective amount of the microcapsule particlecomposition of the present invention.

As described herein, the present invention is well suited for use in avariety of well-known consumer products such as laundry detergent andfabric softeners, liquid dish detergents, automatic dish detergents, aswell as hair shampoos and conditioners. These products employ surfactantand emulsifying systems that are well known. For example, fabricsoftener systems are described in U.S. Pat. Nos. 6,335,315, 5,674,832,5,759,990, 5,877,145, 5,574,179; 5,562,849, 5,545,350, 5,545,340,5,411,671, 5,403,499, 5,288,417, 4,767,547, 4,424,134. Liquid dishdetergents are described in U.S. Pat. Nos. 6,069,122 and 5,990,065;automatic dish detergent products are described in U.S. Pat. Nos.6,020,294, 6,017,871, 5,968,881, 5,962,386, 5,939,373, 5,914,307,5,902,781, 5,705,464, 5,703,034, 5,703,030, 5,679,630, 5,597,936,5,581,005, 5,559,261, 4,515,705, 5,169,552, and 4,714,562. Liquidlaundry detergents which can use the present invention include thosesystems described in U.S. Pat. Nos. 5,929,022, 5,916,862, 5,731,278,5,565,145, 5,470,507, 5,466,802, 5,460,752, 5,458,810, 5,458,809,5,288,431, 5,194,639, 4,968,451, 4,597,898, 4,561,998, 4,550,862,4,537,707, 4,537,706, 4,515,705, 4,446,042, and 4,318,818. Shampoo andconditioners that can employ the present invention include U.S. Pat.Nos. 6,162,423, 5,968,286, 5,935,561, 5,932,203, 5,837,661, 5,776,443,5,756,436, 5,661,118, 5,618,523, 5,275,755, 5,085,857, 4,673,568,4,387,090 and 4,705,681.

Sol-gel precursors, i.e. starting compounds capable of forming gels,suitable for the purposes of the invention are known per se to theexpert. Sol-gel precursors usable in accordance with the invention are,for example, compounds, which are capable of forming gels, such assilicon, boron, aluminum, titanium, zinc, zirconium and vanadium.According to one embodiment, preferred sol-gel precursors are silicon,boron and aluminum compounds, more particularly organosilicon,organoboron and organoaluminum compounds. The precursors can alsoinclude metal alkoxides and b-diketonates

Sol-gel precursors suitable for the purposes of the invention areselected in particular from the group of di-, tri- and/ortetrafunctional silicic acid, boric acid and alumoesters, moreparticularly alkoxysilanes (alkyl orthosilicates), and precursorsthereof.

One example of sol-gel precursors suitable for the purposes of theinvention are alkoxysilanes corresponding to the following generalformula:

(R₁O)(R₂O)M(X)(X′)

wherein X is equal to hydrogen, or —OR₃, and X′ is equal to hydrogen, or—OR₄ and R1, R₁, R₂, R₃ and R₄ independently represent an organic group,more particularly a linear or branched alkyl group, preferably a C₁₋₁₂alkyl. M can be equal to Si, Ti, and Zr.

One example of a preferred sol/gel precursors suitable for the purposesof the invention are alkoxysilanes corresponding to the followinggeneral formula:

(R₁O)(R₂O)Si(X)(X′)

wherein X is equal to hydrogen, or —OR₃, and X′ is equal to hydrogen, or—OR₄ and R1, R₁, R₂, R₃ and R₄ independently represent an organic group,more particularly a linear or branched alkyl group, preferably a C₁₋₁₂alkyl.

According to one embodiment, particularly preferred compounds are thesilicic acid esters tetramethyl orthosilicate (TMOS) and tetraethylorthosilicate (TEOS). A preferred compound includes Dynasylan®(commercially available from Degussa Corporation, Parsippany N.J., USA).Other sol-gel precursors suitable for the purposes of the invention aredescribed, for example, in German Patent Application DE10021165. Thesesol-gel precursors are various hydrolyzable organosilanes such as, forexample, alkylsilanes, alkoxysilanes, alkyl alkoxysilanes andorganoalkoxysilanes. Besides the alkyl and alkoxy groups, other organicgroups (for example allyl groups, aminoalkyl groups, hydroxyalkylgroups, etc.) may be attached as substituents to the silicon.

Recognizing that metal and semi metal alkoxide monomers (and theirpartially hydrolyzed and condensed polymers) such as tetramethoxy silane(TMOS), tetraethoxy silane (TEOS), etc. are very good solvents fornumerous molecules and active ingredients is highly advantageous sinceit facilitated the utilization of this solubility property to load thedissolved molecules or substances in the monomeric precursor solvent orin the hydrolysis-condensation polymer of the monomer solvent.Nonetheless, the present invention may also be used to coat or loadmolecules or active ingredients which can be suspended in theprecursors.

The particle size of the microcapsules may be in the range of 0.01-1000microns in diameter, preferably 0.1-100 microns in diameter and morepreferably 1-10 microns in diameter.

The wall thickness of the capsules can be controlled by varying theamount of monomer added. The ratio of monomer, such as TEOS, to that ofoil phase, such as fragrance, may vary from about 2 to about 80 weightpercent, preferably from about 5 to about 60 weight percent, morepreferably from about 10 to about 50 weight percent, most preferablyfrom about 15 to about 40 weight percent.

The water in the microcapsule particle composition may also be removedto provide a final product in powder form.

According to one embodiment of the present invention, the spray drycarriers can be selected from the group consisting of carbohydrates suchas chemically modified starches and/or hydrolyzed starches, gums such asgum arabic, proteins such as whey protein, cellulose derivatives, clays,synthetic water-soluble polymers and/or copolymers such as polyvinylpyrrolidone, polyvinyl alcohol. The spray dry carriers may be present inan amount from about 1% to about 50%, more preferably from about 5% toabout 20%.

Optionally, a free flow agent (anticaking agent) of silicas which may behydrophobic (i.e. silanol surface treated with halogen silanes,alkoxysilanes, silazanes, siloxanes, etc. such as Sipernat D17, AerosilR972 and R974 (available from Degussa), etc.) and/or hydrophilic such asAerosil 200, Sipernat 22S, Sipernat 50S, (available from Degussa),Syloid 244 (available from Grace Davison), may be present from about0.01% to about 10%, more preferable from 0.5% to about 5%.

Further suitable humectants and viscosity control/suspending agents aredisclosed in U.S. Pat. Nos. 4,428,869, 4,464,271, 4,446,032, and6,930,078 may also be incorporated. Details of hydrophobic silicas as afunctional delivery vehicle of active materials other than a freeflow/anticaking agent are disclosed in U.S. Pat. Nos. 5,500,223 and6,608,017.

As described herein, the spray-dried microcapsule particle compositionis well suited for use in a variety of all dry (anhydrous) products:powder laundry detergent, fabric softener dryer sheets, householdcleaning dry wipes, powder dish detergent, floor cleaning cloths, or anydry form of personal care products (e.g. shampoo powder, deodorantpowder, foot powder, soap powder, baby powder), etc. Because of highfragrance and/or active agent concentration in the spray-dried productsof the present invention, characteristics of the aforementioned consumerdry products will not be adversely affected by a small dosage of thespray-dried products.

The spray drying inlet temperature is in the range of about 150° C. andabout 240° C., preferably between about 170° C. and about 230° C., morepreferably between about 190° C. and 220° C.

The present invention imparts a consumer benefit specifically relatingto the different phase fragrance and/or benefit agent release:long-lasting benefit and/or fragrance perception via control releasefrom capsules and relative immediate benefit and/or fragrance perceptionvia release from water-soluble matrix dissolution. Also the change ofsensory perception can be achieved due to the fragrance encapsulated incapsules could be different from that encapsulated in spray dry matrix.Finally, the high fragrance and/or benefit agent shelf life stability ismade possible when spray-dried particles are placed in anhydrous baseswith a minimal leaching.

All U.S. patents and patent applications cited herein are incorporatedby reference as if set forth herein in their entirety.

The following examples are provided as specific embodiments of thepresent invention. These and additional modifications and improvementsof the present invention may also be apparent to those with ordinaryskill in the art. The particular combinations of elements described andillustrated herein are intended only to represent only a certainembodiment of the present invention and are not intended to serve aslimitations of alternative articles within the spirit and scope of theinvention.

Example 1 Method A: Preparation of Silica Capsule by DirectEmulsification

Twelve grams tetraethyl orthsilicate (TEOS) was mixed with 140 g offragrance oil (to form an oil phase and the mixture was cooled down inan ice-bath. The fragrance is suitable for personal care applications.In a separate vessel, 150 g of 0.5% aqueous surfactant (CTAC: cetyltrimethyl ammonium chloride obtained as 25% solution from AldrichChemical Company, Milwaukee, Wis., USA) solution was prepared bydissolving the needed amount of surfactant in distilled water and wasalso cooled down on an ice-bath. The oil phase was then poured into theaqueous phase and the mixture was homogenized using a high shear mixer(Ultra Turrax T 25 Basic, IKA, Werke). Four drops of defoamer was addedto suppress the foam generated. The pH of the system is maintainedaround 3.9. The system was the left at room temperature and cured for anextended period of time. The capsule formed was well dispersed andgenerally has a particle size ranging from submicron to one hundredmicron depending on the emulsifier and shear rate used.Capsule can also be prepared without cooling the various mixtures. Theamount of wall material can be easily adjusted by adjusting the amountof TEOS.

Example 2 Method B: Preparation of Silica Capsule by DirectEmulsification of Oil, then Adding the TEOS: The 1-Step Post-AdditionProcess.

Step One. Preparation of Fragrance Emulsion.

140 g fragrance oil was placed in round bottom vessel and was cooleddown in an ice-bath. In a separate vessel, 0.5% of aqueous surfactantsolution (150 g) was prepared by dissolving the needed amount of solidsurfactant in distilled water and was also cooled down on an ice-bath.The oil phase was then poured into the aqueous phase and the mixture washomogenized with a high shear mixer (Ultra Turrax T 25 Basic, IKA,Werke). Four drops of defoamer was added to suppress the foaminggenerated.

Step Two. Addition of TEOS to the Fragrance Emulsion.Twenty four gram of wall forming TEOS was weighted out in a clean anddry vessel and was transferred into a dropping funnel. It was then addeddrop wise into the fragrance emulsion prepared in Step one underconstant mixing. The mixing speed was reduced once the addition of TEOSwas complete. The system was then left at room and cured for an extendedperiod of time. The pH of the system is maintained around 3.9. Thecapsule formed was well dispersed and generally has a particle sizeranging from submicron to one hundred micron depending on the emulsifierand shear rates used.

Example 3 Method C: Preparation of Silica Capsule by PreparingConcentrated Fragrance Emulsification, Diluting the Fragrance Emulsionto Desired Concentration, and Adding the TEOS: The 2-Step Post-AdditionProcess

Step One. Preparation of Concentrated Fragrance Emulsion.

This was achieved the same as step one on Example 4 using 140 g of thesame fragrance.

Step Two: Preparation of Diluted Fragrance Emulsion.

This was achieved the by blending the emulsion prepared in step one ofexample 3 with the desired amount of water to generate the desiredconcentration.

Step Three. the Formation of Silica Capsules by Adding TEOS to theDiluted Fragrance Emulsion.

The amount of TEOS added in this step is normally determined by the wallpolymer level needed and the amount of wall forming TEOS can be variedfrom 1% to 30% of the finished formulation.

Typically, the desired amount TEOS (24 g in this example) was weightedout and placed in a clean and dry dropping funnel. The TEOS was thenadded drop wise into the fragrance emulsion prepared in step two underconstant mixing. The mixing speed was reduced once the addition of TEOSwas complete. The system was the left at room and cured for an extendedperiod of time. The pH of the system is maintained around 3.9.

The capsule formed was well dispersed and generally has a particle sizeranging from submicron to one hundred micron depending on the emulsifierand shear rates used.

Example 4 Method D: Preparation of Silica Capsule by Adding TEOSEmulsion to Fragrance Emulsion

Step One. Preparation of Fragrance Emulsion.Four hundred grams of fragrance (Rapid leach, IPC, 31744979, IFF)emulsion containing 40% fragrance oil was prepared by emulsifying 160 gfragrance oil into 240 of surfactant (CTAC) solution. This fragranceemulsion can be further diluted to the desired fragrance concentration.

Step Two: Preparation of TEOS Emulsion.

Twenty four grams of TEOS was emulsified into a cooled aqueoussurfactant solution (50 g) under shearing to give the TEOS emulsion. Thesurfactant used is a nonionic surfactant Witconol NP-90 (Akzo NobelSurface Chemistry, Chicago, Ill., USA).Step Three. Silica Capsule Formation by Adding TEOS Emulsion toFragrance Emulsion.The TEOS emulsion prepared in step two was added into the fragranceemulsion prepared in step one under constant mixing. The mixing speedwas reduced once the addition of TEOS emulsion was complete. The systemwas the left at room temperature and cured for an extended period oftime. The capsules formed were well dispersed and generally have aparticle size ranging from submicron to one hundred micron depending onthe emulsifier and shear rates used.

Example 5 Method E: Preparation of Silica Capsule Using Sol-Gel Polymerby Pre-Hydrolysis of TEOS and Emulsification of Fragrance Oil

Step one. Preparation of sol-gel polymer by hydrolysis of TEOS. Fiftygrams of TEOS was dissolved in 17.43 g of DI H₂O and 44.35 g of Ethanol.The pH of the mixture was then adjusted to a pH of 2 with a 10% solutionof HCl. The mixture was allowed to stir for 15 minutes after this time.The mixture was blended with fragrance once the phase separationdisappeared.Step two: Preparation of silica capsule. Two hundred seventy grams offragrance oil suitable for personal care application was blended with 72g of the sol-gel precursors and the mixture was directly emulsified intocooled an aqueous surfactant solution under shearing to give thefragrance emulsion. The system was the left at room and cured for anextended period of time. The capsules formed were well dispersed andgenerally had a particle size ranging from submicron to one hundredmicron depending on the emulsifier and shear rates used.

Example 6 Modification of Silica Capsules Using Second SphereComplexation Using Polyethyleneimine (PEI) Polymer

Preparation of neutralized PEI solution: A 50% PEI (MW ˜750 kD, AldrichChemical Company, Milwaukee, Wis., USA) solution was pH adjusted to ˜4using concentrated HCl. The effective concentration of PEI was at 22%after the addition of HCl was complete.Addition of PEI to silica capsule slurry: One hundred gram of the silicacapsule slurry (from Example 1) was continuously stirred while 20 g ofPEI solution (˜22%, pH ˜4) was slowly added. The mixture was stirred atroom temperature overnight.

Example 7 Second Sphere Modification of Silica Capsules with a NonionicAmine Oxide Surfactant

Preparation of neutralized CDO special solution: Ammonyx® CDO Special,or cocoamidopropylamine oxide, was obtained from the Stephan Company(Chicago, Ill., USA) and contains 32.5% active ingredient. Theconcentrated solution was pH adjusted to ˜4 using 10N HCl. The finalconcentration of amine oxide was 29% after it was neutralization.Addition of CDO special to silica capsule slurry: One hundred of silicacapsule slurry (from Example 1) was continuously stirred while 5.8 g ofAmmonyx® CDO Special solution (˜29% active, pH ˜4) was slowly added. Themixture was stirred at room temperature overnight and used for furtherapplication studies.

Example 8 Second Sphere Modification of Silica Capsules with an AnionicSurfactant: ammonium lauryl ether sulfate (STEOL CA-300)

Preparation of neutralized STEOL CA-300 solution: Ammonium lauryl ethersulfate solution (STEOL® CA-330) was obtained from Stephan (Chicago,Ill.) which has 28% active. The pH of the solution was adjusted to ˜pH 4using 1N HCl. With the addition of HCl, the concentration of the activecompounds decreased to ˜27%.Addition of STEOL to silica capsule slurry: 100 g of silica capsuleslurry (from Example 1) of 100 g was continuously stirred while 6.3 g ofSTEOL® CA-330 solution (˜27% active, pH ˜4) was added to it and themixture was stirred overnight and used for further experiments.

Example 9 Second Sphere Modification of Silica Capsules with InorganicNanoparticle: Zinc Oxide

To 100 g Silica capsule slurry (from Example 1) was added 0.1 g Z-COTEHP1 (BASF), the particle size of ZnO was less than 200 nm. The mixturewas overhead stirred at room temperature overnight.

Example 10 Evaluation of Capsule Stability by Microscopy

The stability of the capsules was evaluated by diluting the slurry withwater. The diluted sample was placed on a microscopic slide andmonitored overnight. The results are given in FIG. 10 A to 10 F. Themicroscopic picture in FIG. 10A depicts well formed silica capsules asfresh sample in water. Some breakage of the capsules was seen after thecapsules were dried overnight on a microscopy slide as illustrated inFIG. 10B. Damage to capsules was also observed using SEM (FIG. 10 C) andwhen a vacuum was applied and the capsules was dried to some extent.An optical picture of sample prepared using example 6 was presented inFIG. 10 D and it clearly shows the capsules retained their structuralintegrity after drying overnight in a microscopy slide. The picturetaken using SEM further confirmed that the robustness of the capsuleswas dramatically improved as compared with FIG. 10C.The procedure in example 7 was also used to prepare stabilized capsuleslurry and the optical (FIG. 10F) and SEM (10G) showed that capsulesretained its structural integrity after being dried overnight.We also found the second sphere modification of silica capsules usingZnO can increase the stability of the capsules and the result isdemonstrated in FIG. 10H.

Example 11 Encapsulation Performance of Mechanically Stable SilicaCapsules

The sample prepared in example 6 was evaluated for its performance byhead space analysis. The fragrance capsule slurry was diluted withdistilled water to yield a mixture containing 0.4% capsule slurry. Onegram each of the diluted capsule slurry was directed applied to eachside of a 4×6 fabric swatch. Three samples were evaluated. They are neatfragrance (neat), capsule from example 3 (no modification) without thesecond sphere modification, and a sample from example 6 were prepared(modified capsule). The swatches were air-dried over night and theheadspace of the fabrics was analyzed before and after stirring withsteel ball bearings to rupture intact capsules. The results are given intable 1 below.

TABLE 1 Encapsulation performance of the modified silica capsules Headspace Head space Ratio of Sample Unstirred Stirred Stirred/UnstirredNeat fragrance 4400 6600 1.5 Unmodified capsules 3600 8050 2.23 Modifiedcapsules 2350 16000 6.80

It can be clearly seen that there is a dramatic increase in headspaceafter the capsules were disrupted by milling in the modified silicacapsules. The ratio of stirred/unstirred sample increased by 200 percentin the modified capsules. This demonstrated that increase perfumeryperception can be achieved once the capsules are deposited on fabric.

Example 12 Sensory Performance of Mechanically Stable Silica Capsules

The sample prepared in example 6 was evaluated for its performance by antrained internal panel. The fragrance capsule slurry was diluted withdistilled water to yield a mixture containing 0.4% capsule slurry. Onegram each of the diluted capsule slurry was directed applied to eachside of a 4×6 fabric swatch. The swatches were air-dried over night andthe evaluated by the internal panel of 12 judges. The fragranceintensity is rated from a scale ranging from 0 to 30. A numerical valueof 5 would suggest the fabric only produce very week intensity while avalue of 30 indicates the subject generate a strong smell. Three sampleswere evaluated. They are neat fragrance (neat), capsule from example 3(no modification) without the second sphere modification, and a samplefrom example 6 were prepared (modified capsule). The results are inTable 3.

TABLE 3 Contrasting the Sensory performance of capsules with that ofneat fragrance and unmodified capsules Pre-rubbing Post-rubbing Samplesintensity intensity I_(post)/_(Ipre) Neat 6.0 6.5 1.1 Unmodified 6.0 6.01.0 capsules Modified 4.0 16.0 4.0 capsulesIt is quite apparent the modified silica fragrance capsules producedmuch greater fragrance intensity at post-rubbing stages stage. The ratioof intensity (I_(post)/_(Ipre)) in the coated capsule is four times thatof the neat and uncoated capsules. This demonstrates that the modifiedfragrance capsules prepared with the current invention are able toretain the fragrance effectively and are capable of delivering the fullconsumer benefits of the fragrance products.

Example 13 Benefit of the Microcapsule Particle Composition in aPersonal Care Application

This example illustrates the application benefit of the capsulesprepared by the process in Example 9 in anti-perspirent (AP) roll-onbase. Fragrance capsule slurry was prepared using the process describedin Example 9. The capsule slurry was dispersed in a AP-roll base at 0.5%neat fragrance equivalent. The base typically contained 1 to 3% anionicsurfactant, 10 to 20%, aluminum chlorohydrate, less than 1% silica, 1 to2% Helianthus Annuus and water.

The prepared product containing the capsule (100 ul) in AP roll-on basedwas applied to the forearm of six panelists and the fragrance intensitywas evaluated immediately after application and five hours afterapplication with rubbing by 20 trained intensity judges and data wasanalyzed statistically. The fragrance intensity is rated from a scaleranging from 0 to 30. A numerical value of 5 would suggest the substrateonly produce very week intensity while a value of 30 indicates thesubject generate a strong smell.

It was found that, after rubbing the product containing capsulegenerated greater fragrance intensity before rubbing after five hoursand significantly greater intensity after rubbing than a productcontaining neat fragrance only. The post rubbing intensity of thecapsule product is 150% that of the neat fragrance product. Whenrepeated measures analysis of variance is used to analyze the data.There is significant difference between the capsule and neat whensignificance level is set at p<0.01. Results are provided below in Table4. This clearly demonstrate that the modified capsule in the currentinvention can deliver superior consumer befits when compared to the useof neat fragrance.

TABLE 4 Fragrance benefits of the capsules prepared by current inventionFragrance Fragrance Fragrance intensity 5 intensity 5 Ratio intensityhours after hours after of immediately application application I_(p),after without with rubbing, neat/ Sample application rubbing, I_(pre)I_(post) I_(capsule) Neat 18.0 8.7 7.0 1 fragrance Capsules 16.0 9.210.5 1.5 prepared by the current invention from example 9Storage test conducted simultaneously indicated that there is only 10%fragrance leach out of the capsule after 5 weeks at 37° C. These resultsclearly established the excellent consumer benefits and long termstability of the capsules prepared by our invention.

1. A process for preparing a microcapsule particles containing an activematerial in the core comprising the steps of a. Preparing a mixture ofan appropriate amount of sol-gel precursor and an active material; b.Cooling the mixture obtained in step a; c. Preparing a surfactantsolution by dissolving a surfactant in water; d. Cooling the surfactantsolution obtained in step c; e. Adding the sol-gel precursor andfragrance oil mixture obtained in step a to the surfactant solutionobtained in step c; f. Homogenizing the mixture of sol-gel precursor,fragrance oil and surfactant solution obtained in step e; g. Adding adefoamer to the homogenized mixture obtained in step f; h. Curing themixture to form the microcapsule particles; and i. Modifying themicrocapsule particles with a second sphere complexation to form acoated microcapsule particle.
 2. The process of claim 1 wherein thesecond sphere complexation is selected from the group consisting of apolyethyleneimine (PEI) polymer, an amine oxide, cocoamidopropylamineoxide, ammonium lauryl ether sulfate, an inorganic zinc oxide, andmixtures thereof.
 3. The process of claim 1 wherein the active materialis a fragrance.
 4. The process of claim 1 wherein the sol-gel precursoris selected from a metal or semi-metal alkoxide monomer, or metal estermonomer, semi-metal ester monomer or alkoxysilanes monomer correspondingto the general formula: (R₁O)(R₂O)M(X)(X′) wherein M is equal to Si, Ti,and Zr; wherein X is equal to hydrogen, or —OR₃, and X′ is equal tohydrogen, or —OR₄ and R1, R₁, R₂, R₃ and R₄ independently represent alinear or branched alkyl group, preferably a C₁₋₁₂ alkyl.
 5. The processof claim 1 wherein the sol-gel precursor is selected from the groupconsisting of TMOS, TEOS and mixtures thereof.
 6. The process accordingto claim 1 further comprising the step of removing the water to obtain afinal product in a powder form.
 7. The microcapsule particle compositionobtained by the process of claim 1 in powder form.
 8. A personal careproduct comprising the microcapsule particle composition preparedaccording to claim
 1. 9. The personal care product of claim 8 whereinthe personal care product is selected from the group consisting ofshampoos, hair rinses, body washes, soaps, hand sanitizersanti-perspirant and deodorants.
 10. The personal care product of claim 8wherein the product is an anti-perspirant.
 11. A process for preparing amicrocapsule particle composition comprising the steps of a. Adding afragrance oil to an aqueous surfactant solution to form a mixture; b.Homogenizing the mixture obtained in step a to form a fragranceemulsion; c. Adding a sol-gel precursor dropwise to the fragranceemulsion under continuous mixing; d. Curing the mixture at roomtemperature to form the microcapsule particle composition, e. Modifyingthe microcapsule particles with a second sphere complexation to form acoated microcapsule particle composition.
 12. The process of claim 11wherein the second sphere complexation is selected from the groupconsisting of a polyethyleneimine (PEI) polymer, an amine oxide,cocoamidopropylamine oxide, ammonium lauryl ether sulfate, an inorganiczinc oxide, and mixtures thereof.
 13. The process of claim 11 whereinthe active material is a fragrance.
 14. The process of claim 11 whereinthe sol-gel precursor is selected from a metal or semi-metal alkoxidemonomer, or metal ester monomer, semi-metal ester monomer oralkoxysilanes monomer corresponding to the general formula:(R₁O)(R₂O)M(X)(X′) wherein M is equal to Si, Ti, and Zr; wherein X isequal to hydrogen, or —OR₃, and X′ is equal to hydrogen, or —OR₄ and R1,R₁, R₂, R₃ and R₄ independently represent a linear or branched alkylgroup, preferably a C₁₋₁₂ alkyl.
 15. The process of claim 11 wherein thesol-gel precursor is selected from the group consisting of TMOS, TEOSand mixtures thereof.
 16. The process according to claim 11 furthercomprising the step of removing the water to obtain a final product in apowder form.
 17. The microcapsule particle composition obtained by theprocess of claim 11 in powder form.
 18. A personal care productcomprising the microcapsule particle composition prepared according toclaim
 1. 19. The personal care product of claim 18 wherein the personalcare product is selected from the group consisting of shampoos, hairrinses, body washes, soaps, hand sanitizers, anti-perspirant anddeodorants.
 20. The personal care product of claim 19 wherein theproduct is an anti-perspirant.
 21. A process for preparing amicrocapsule particle composition comprising the steps of: a. Adding afragrance oil to an aqueous surfactant to form a mixture; b.Homogenizing the mixture obtained in step a to form a fragranceemulsion; c. Adding an appropriate amount of water to the fragranceemulsion obtained in step b to achieve the desired concentration; d.Adding a sol-gel precursor to the diluted fragrance emulsion obtained instep c dropwise under constant mixing; e. Curing the mixture at roomtemperature until the microcapsule particle composition is formed; andf. Modifying the microcapsule particles with a second spherecomplexation to form a coated microcapsule particle composition.
 22. Theprocess of claim 21 wherein the second sphere complexation is selectedfrom the group consisting of a polyethyleneimine (PEI) polymer, an amineoxide, cocoamidopropylamine oxide, ammonium lauryl ether sulfate, aninorganic zinc oxide and mixtures thereof.
 23. The process of claim 21wherein the active material is a fragrance.
 24. The process of claim 21wherein the sol-gel precursor is selected from a metal or semi-metalalkoxide monomer, or metal ester monomer, semi-metal ester monomer oralkoxysilanes monomer corresponding to the general formula:(R₁O)(R₂O)M(X)(X′) wherein M is equal to Si, Ti, and Zr; wherein X isequal to hydrogen, or —OR₃, and X′ is equal to hydrogen, or —OR₄ and R1,R₁, R₂, R₃ and R₄ independently represent a linear or branched alkylgroup, preferably a C₁₋₁₂ alkyl.
 25. The process of claim 21 wherein thesol-gel precursor is selected from the group consisting of TMOS, TEOSand mixtures thereof.
 26. The process according to claim 21 furthercomprising the step of removing the water to obtain a final product in apowder form.
 27. The microcapsule particle composition obtained by theprocess of claim 21 in powder form.
 28. A personal care productcomprising the microcapsule particle composition prepared according toclaim
 21. 29. The personal care product of claim 28 wherein the personalcare product is selected from the group consisting of shampoos, hairrinses, body washes, soaps, hand sanitizers anti-perspirants anddeodorants.
 30. The personal care product of claim 29 wherein theproduct is an anti-perspirant.
 31. A process for preparing amicrocapsule particle composition comprising the steps of: a. Preparinga fragrance emulsion comprising the steps of emulsifying a fragrance oilinto surfactant solution; b. Preparing a sol-gel precursor emulsion byemulsifying a sol-gel precursor and an aqueous surfactant solution; c.Adding the sol-gel precursor emulsion formed in step b to the fragranceemulsion obtained in step a under constant mixing d. Curing the mixtureobtained in step c at room temperature until the microcapsule particlecomposition has formed; and e. Modifying the microcapsule particles witha second sphere complexation to form a coated microcapsule particlecomposition.
 32. The process of claim 31 wherein the second spherecomplexation is selected from the group consisting of apolyethyleneimine (PEI) polymer, an amine oxide, cocoamidopropylamineoxide, ammonium lauryl ether sulfate, an inorganic zinc oxide andmixtures thereof.
 33. The process of claim 31 wherein the activematerial is a fragrance.
 34. The process of claim 31 wherein the sol-gelprecursor is selected from a metal or semi-metal alkoxide monomer, ormetal ester monomer, semi-metal ester monomer or alkoxysilanes monomercorresponding to the general formula: (R₁O)(R₂O)M(X)(X′) wherein M isequal to Si, Ti, and Zr; wherein X is equal to hydrogen, or —OR₃, and X′is equal to hydrogen, or —OR₄ and R1, R₁, R₂, R₃ and R₄ independentlyrepresent a linear or branched alkyl group, preferably a C₁₋₁₂ alkyl.35. The process of claim 31 wherein the sol-gel precursor is selectedfrom the group consisting of TMOS, TEOS and mixtures thereof.
 36. Theprocess of claim 31 wherein an appropriate amount of water to thefragrance emulsion obtained in step b to achieve a diluted fragranceemulsion.
 37. The process according to claim 31 further comprising thestep of removing the water to obtain a final product in a powder form.38. The microcapsule particle composition obtained by the process ofclaim 31 in powder form.
 39. A personal care product comprising themicrocapsule particle composition prepared according to claim
 31. 40.The personal care product of claim 39 wherein the personal care productis selected from the group consisting of shampoos, hair rinses, bodywashes, soaps, hand sanitizers, anti-perspirants and deodorants.
 41. Thepersonal care product of claim 40 wherein the product is ananti-perspirant.